Traders Bet VIX Calm Won't Last; History Suggests Otherwise

After years of wild price swings in the stock market, the plunge in volatility in recent months has many investors thinking the calm can't last.

In mid-March, the Chicago Board Options Exchange's Volatility Index, which measures the expected volatility in the Standard & Poor's 500-stock index, fell to a six-year low of 11.30. The VIX has averaged 13.52 so far in 2013, levels not seen since before the U.S. financial crisis. The...